Textile material sized with zirconium salt of water-soluble carboxyalkyl cellulose



.mimnhi Patented Sept. 1, 1953 TEXTILE MATERIAL SIZED WITH ZIR- CONIUM SALT OF WATER-SOLUBLE CARBOXYALKYL CELLULOSE John H. Elliott, Wilmington, Del., assignor to Hercules Powder Company, Wilmington, Del., a corporation of Delaware No Drawing. Application March 9, 1948, Serial No. 13,952

3 Claims. (Cl. 117-1395) This invention relates to textile materials sized with an insoluble sizing deposit and more particularly to a textile material sized with a watersoluble carboxyalkyl cellulose derivative insolubilized by a Zirconium salt and to the process of preparing such a material.

Prior art methods of sizin cloth with carboxyalkyl cellulose derivatives have involved a treatment of the cloth with alkali-soluble type low-substituted carboxyalkyl cellulose derivatives followed by treatment with an acid or salt to precipitate and insolubilize the cellulose derivative in the cloth. The low-substitution alkalisoluble types of carboxyalkyl cellulose derivatives have been employed in prior art methods because 1 of the relative ease of insolubilizing by treatment the carboxyalkyl cellulose derivative to the cloth c has necessarily been made from alkaline solutions containing as high as NaOH due to the low substitution of the cellulose derivative, i. e., below about 0.5 carboxyalkyl group per anhydroglucose unit. Such processes are therefore limited to the treatment of textile materials, such as cotton, which are not disintegrated by these alkaline solutions. There is the further disadvantage that textile materials so treated have a very limited resistance to repeated launderings. This results from the softening and disintegratin effect of alkaline launderin treatments on the acid or salt insolubilized carboxyalkyl cellulose derivatives which have been employed in prior art methods.

It is therefore an object of this invention to provide a method of treating textiles with carboxyalkyl cellulose derivatives to give them a greatly improved permanent finish.

A further object of this invention is to provide a method of treating textiles with carboxyalkyl cellulose derivatives to give them a permanent finish having greatly improved resistance to laundering and to acid and alkaline solutions.

A still further object of this invention is the provision of a permanently sized textile material which has improved resistance to laundering and to acid and alkaline solutions.

Another object of this invention is the provision of a permanently sized textile material which has increased water repellency.

Now, in accordance with the present invention it has been found that permanently sized textile materials having greatly improved resistance to laundering and to acids and alkalies may be prepared by a process which involves treating the textile material with a water-soluble carboxyalkyl cellulose derivative followed by a treat ment with a zirconium salt to precipitate and insolubilize the carboxyalkyl cellulose derivatives in the textile. Applicant has found that the zirconium salt of water-soluble carboxyalkyl cellulose derivatives is substantially insoluble in both concentrated'acid and concentrated alkali solutions, and that cloth sized with this salt is extremely resistant to alkaline laundering. After precipitation and insolubilization of the carboxyalkyl cellulose zirconium salt in the textile material any excess zirconium salt is removed from the textile by washing with a mild alkaline solution as, for example, a dilute sodium carbonate 1 solution. Increased water repellency of the sized textile material may be obtained at this stage by incorporating with the alkaline bath a small amount of a water-soluble soap.

In eneral the procedure for preparation of I the sized textile material in accordance with the present invention will involve thoroughly wetting the fabric wtih the water solution of the carboxyalkyl cellulose derivative, squeezing the fabric wet with the solution to the desired add-on,

treating the fabric with the zirconium salt for Example I Sodium carboxymethyl cellulose having a viscosity characteristic of 25 to 50 cps. in 2% concentration in water and a degree of substitution of approximately 0.7 carboxymethyl group per anhydroglucose unit was dissolved in water to produce a 2% solution. This solution was applied to a piece of kier-boiled, bleached and mercerizedcotton cloth x 80 threads per inch, l yds. per 1b.) by dipping the cloth in the solution and then passing the impregnated sample between squeeze rolls to yield a solution add-on of approximately 100% based on the weight of the untreated cloth. The treated cloth was immediately placed in a boiling 10% solution of sodium zirconyl sulfate in water and allowed to remain there for 15 minutes. Upon removal from the boiling solution of sodium zirconyl sulfate the cloth was placed in a boiling solution containing 0.3% sodium carbonate and .3% tallow soap. After 10 minutes in this boiling solution the cloth was removed, rinsed, dried, weighed and examined for permanency of the finish. The sized cloth contained an add-on of 8 to 10% of an insolubilized sizing deposit containing as the essential ingredient the zirconium salt of carboxymethyl cellulose and exhibited good flexibility and hand, and had somewhat more body than untreated samples. The finish was resistant to strong aqueous acid and stron aqueous alkali solution and had not been destroyed after twelve standard laundering cycles in the Launder- Ometer.

Example II The process as outlined in Example I was followed using a 2% solution of sodium carboxymethyl cellulose having a viscosity characteristic of 400 to 600 cps. in 2% concentration in water and a degree of substitution of approximately 0.7 carboxymethyl group per anhydroglucose unit. The sized cloth had an add-on of 10% of an insoluble sizing deposit similar to that of Example I and exhibited substantially the same laundering resistance.

Example MI The process as outlined in Example I was followed using a 2% water solution of sodium carboxymethyl cellulose having a degree of substitution of about 0.5 carboxymethyl group per anhydroglucose unit. The sized cloth had an addon of 9 to 10% of an insoluble sizing deposit similar to that of Example I and exhibited substantially the same laundering resistance.

Example V The process as outlined in Example I was followed using a 2% water solution of sodium carboxymethyl cellulose having a viscosity characteristic of 400 to 600 cps. in 2% concentration in water and a degree of substitution of about 1.2 carboxymethyl groups per anhydroglucose unit. The sized cloth had an add-on of 10% of an insoluble sizing deposit similar to that of Example I and exhibited substantially the same laundering resistance.

Example VI The process as outlined in Example I was followed using a 0.5% water solution of sodium carboxymethyl cellulose having a viscosity characteristic of 25 to 50 cps. in 2% concentration in water and a degree of substitution of about 0.7 carboxymethyl group per anhydroglucose unit. The sized cloth had an addeon of of an intreated textile.

The process as outlined in Example I was followed except that the insolubllizing bath of sodium zirconyl sulfate was maintained at 60 C. and the concentration of the sodium carboxymethyl cellulose solution was 4%. The sized cloth had an add-on of 15% of an insoluble sizing deposit similar to that of Example I and exhibited substantially the same laundering resistance.

In addition to exhibiting remarkable permanence to the laundering tests the sized textiles of Examples I to VII also exhibited a water repellency which was retained through as many as four complete laundering cycles before this effect was materially reduced.

Applicants invention involves a first treatment of the textile fabric with a solution of a watersoluble carboxyalkyl cellulose derivative. Suitable water-soluble derivatives will include, for example, the sodium, potassium lithium and ammonium salts of carboxymethyl, carboxyethyl and carboxypropyl cellulose. The degree of substitution of the carboxyalkyl cellulose derivative must be not less than about 0.5 carboxyalkyl group per anhydroglucose unit. Generally the degree of substitution will vary from about 0.5 to about 2.0 and preferably from about 0.7 to 1.2 carboxyalkyl groups per anhydroglucose unit.

The carboxyalkyl celluolse derivative may be of any viscosity type. In most cases the viscosity type selected will be governed by the solids required for a particular application. Generally viscosity types varying from about 10 cps. to about 2000 cps. will be found satisfactory.

The carboxyalkyl cellulose derivative may be applied to the textile material by any suitable method such as by dipping, spraying, padding rolls or doctor blades. However, the preferred method of application comprises immersing or dipping the textile fabric in a water solution of the carboxyalkyl cellulose derivative followed by squeezing to obtain the desired add-on. If desired, several successive dipping and squeezing operations may be employed. In general, temperatures utilized in this operation will be normal room temperature. However, any temperature above the freezing point and below the boiling point of the carboxyalkyl cellulose derivative solution may be employed.

The concentration of the carboxyalkyl cellulose derivative in the aqueous solution will vary from about 0.5% to about 10% or higher. The preferred concentration will be between about 2% and about 5%.

The textile wetted with the solution of the carboxyalkyl cellulose derivative will ordinarily contain between about 50% and 350% of solution based on the weight of the untreated textile. Preferably, the textile will contain about of the solution based on the weight of the un- A quantity less than 50% by weight is difficult to obtain short of extreme application of pressure, and amounts greater than 350% are difficult to retain in the cloth.

Following treatment of the textile material with the carboxyalkyl cellulose derivative the material is then treated with a solution of a zirconium salt to precipitate and insolubilize the celluolse derivative. This treatment is preferably accomplished by placing the fabric while still wet with the carboxyalkyl cellulose derivative in a bath of the zirconium salt solution at a temperature which may vary from about 60" C. to about 100 C. and for a time sufficient to effect the precipitation and insolubilization. In general, it hasbeen found that a time varying from about 5 to about 30 minutes and preferably from about to about minutes is satisfactory for this purpose. The preferred zirconium salt for use in the present invention is sodium zirconyl sulfate. However, any zirconium salt that will react with the carboxyl groups of the carboxyalkyl cellulose derivative, such as zirconium oxychloride, zirconium acetate, zirconium sulfate, zirconyl sulfate, zirconyl nitrate, ammonium zirconyl tartrate, ammonium zirconyl citrate, potassium zirconyl oxalate, zirconyl acetate, zirconyl phosphate, or zirconyl formate, may be used.

Generally, an amount of the zirconium salt will be used sufficient to precipitate and insolubilize the carboxyalkyl cellulose derivative retained in the textile material. The optimum permanency of the sizing effect will be obtained when all carboxyalkyl groups have reacted with the zirconium salt. However, it is possible to use amounts which are less than or in excess of such an mount. Usually it is preferable to use a substantial excess to insure the maximum permanency of the sizing effect. The concentration of the zirconium salt solution will generally be about 10%, although this is in no sense critical and may be varied considerably above or below this concentration.

Although it is preferred to utilize a textile still wet with the carboxyalkyl cellulose derivative solution in this insolubilization step, this step may be carried out on a textile material which has been dried following the treatment with the solution of carboxymethyl cellulose derivative.

The amount of add-on of zirconium salt of carboxyalkyl cellulose derivative deposited in the textile material will vary with the particular use to which the textile material is to be put. Where a stiff or starchy effect is desired a larger amount of deposit will be necessary. Where, on the other hand, a soft, full finish is desirable lesser amounts will be required. Ordinarily the amount of sizing zirconium carboxyalkyl cellulose salt will range between about 1% and about 20% of the weight of the untreated cloth and preferably will be between about 5% and about 15% on the same basis.

Following the precipitation of the zirconium salt of carboxyalkyl cellulose derivative in the textile any excess of zirconium salt is washed from the textile in an alkaline bath. This is desirable because excess zirconium salt if allowed to remain in the textile might have an undesirable tendering effect on the textile. Any alkaline bath, such as dilute sodium carbonate, sodium meta-silicate, trisodium phosphate, sodium hexametaphosphate, etc., is suitable for this purpose. Preferably the alkaline bath will contain from about 0.1% to about 1.0% of the alkaline material and in addition about the same amount of a water-soluble soap, such as tallow soap, sodium stearate, sodium oleate, etc. The addition of the water-soluble soap increases Water repellency and hence is desirable where such a finish is desired. Washing is usually done at elevated temperatures and preferably at the boiling point of the solution.

It is preferred to transfer the textile material from the zirconium salt bath to the alkaline wash bath while still wet with zirconium salt solution. However, the sized textile material may be dried 6 following the insolubilization treatmentvvlth zirconium salt, and the alkaline wash treatment may be carried out on this dried, sized textile.

Following the alkaline wash the textile cloth is rinsed and dried and is then in condition for use. The process as described is adaptable to a continuous operation wherein the textile material is continuously passed through successive baths of carboxyalkyl cellulose derivative, zirconium salt solution, and alkaline wash, followed by rinsing, drying and calendaring.

One of the outstanding advantages of the present invention is that it permits the use of a water solution of the carboxyalkyl cellulose derivative, thus eliminating the necessity for using caustic treating baths. It further permits the elimination of an intermediate acid treatment to precipitate the size and also permits the use of a wider range of textile materials. The permanently sized textile is highly resistant to acids and alkalies and to alkaline laundering. Textile cloths permanently sized in accordance with this invention are particularly adaptable to such applications as filter cloths, etc., where very heavy wear and some chemical action are encountered.

The laundering test employed in evaluating the permanence of the zirconium carboxyalkyl cellulose sizing material is a standard test employed in the textile trade. One laundering cycle consists of four ten-minute washes with 0.3% Arctic crystal tallow soap at 110 F. in the Launder-Ometer. Individual 6 in. x 6 in. samples of the textile under test are placed in separate one-pint bottles with twenty steel balls and cc. of soap solution and rotated in the Launder- Ometer. The Launder-Ometer rotates at 42 R. P. M. during the test. Cloth samples are weighed initially and after each cycle to determine loss in weight. The Launder-Ometer is a standard piece of test equipment manufactured by the Atlas Scientific Instruments 00., Chicago, Illinois, and is well known in the textile field.

The viscosity characteristic of the carboxyalkyl cellulose derivative is measured by the falling ball method at 25 C., employing a in. steel ball falling freely through 10 inches of the solution of carboxyalkyl cellulose derivative confined in a vertical tube 1 inch in diameter (inside diameter) and is expressed in centipoises. Viscosity types up to and including the 400-600 cp. type employ 2% by weight solutions in water for making this test. Higher viscosity types employ 1% solutions.

What I claim and desire to protect by Letters Patent is:

1. A permanently sized textile comprising a textile and as sizing therefor an insoluble sizing deposit of the zirconium salt of carboxymethyl cellulose, said carboxymethyl cellulose having between about 0.5 and about 2.0 carboxymethyl groups per anhydroglucose unit, said sizing deposit being resistant to laundering and insoluble in acid and alkaline media.

2. A permanently sized textile comprising a textile and as sizing therefor an insoluble sizing deposit of the zirconium salt of carboxymethyl cellulose, said carboxymethyl cellulose having between about 0.7 and about 1.2 carboxymethyl groups per anhydroglucose unit, said sizing deposit being resistant to laundering and insoluble in both acid and alkaline media.

3. A permanently sized textile comprising a textile and as sizing therefor an insoluble sizing deposit of the zirconium salt of a water-soluble carboxyalkyl cellulose derivative having between 7 about 0.5 and about 2.0 carboxyalkyl groups per anhydroglucose unit, said sizing deposit being resistant to laundering and insoluble in both acid and alkaline media. JOHN H. ELLIOTT.

' 'References Cited in the file of this patent UNITED STATES PATENTS 8 Number Name Date 2,420,949 Hager et al May 20, 1947 Edelstein Aug. 26, 1947 110-114, March 2, 1942.

Sodium Carboxymethyl Cellulose, National 0 Paint, Varnish 8: Lacquer Assoc., Circular 688,

pages 191-194, August 1944. 

1. A PERMANENTLY SIZED TEXTILE COMPRISING A TEXTILE AND AS SIZING THEREFOR AN INSOLUBLE SIZING DEPOSIT OF THE ZIRCONIUM SALT OF CARBOXYMETHYL CELLULOSE, SAID CARBOXYMETHYL CELLULOSE HAVING BETWEEN ABOUT 0.5 AND ABOUT 2.0 CARBOXYMETHYL GROUPS PER ANHYDROGLUCOSE UNIT, SAID SIZING DEPOSIT BEING RESISTANT TO LAUNDERING AND INSOLUBLE IN ACID AND ALKALINE MEDIA. 